[Bug c++/20293] New: namespace name lost

[Bug c++/20293] New: namespace name lost

[igodard at pacbell dot net]

In:
namespace hide {
    int k;
    }

namespace {
    int i;
    namespace hide {
        int j;
        }
    }

void F(int) {}

int main() {
    F(i);
    F(hide::j);
    }

you get:

~/ootbc/members/src$ g++ foo.cc
foo.cc: In function `int main()':
foo.cc:16: error: `hide' has not been declared
foo.cc:16: error: `j' undeclared (first use this function)
foo.cc:16: error: (Each undeclared identifier is reported only once for each
function it appears in.)

i.e. the lookup for "hide" fails whereas a simple variable "i" is found.

My (probably erroneous) understanding is that the anonymous namespace has no 
impact on name scope; exports all names declared within it to filescope; and 
simply replaces the old "static" to prevent cluttering the linker namespace. 
That seems to be the case with "i". However, if that rule were applied to "hide" 
then the two "hide"s would be at the same level and would merge as namespaces 
do, rather than the inner one being hidden as happened. This problem arose 
because I was trying to declare a filescope name ("j") in a way that *neither* 
cluttered the compiler's space nor the linkers. 

If this is in fact an error, please change this report to a complaint about the 
diagnostic.

Ivan

-- 
           Summary: namespace name lost
           Product: gcc
           Version: 3.4.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: igodard at pacbell dot net
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20293

[Bug c++/20293] ambiguous namespace and diagnostic, unamed namespace

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2005-03-02 23:01 -------
Confirmed, this is invalid code as the namespace hide is ambiguous but the diagnostic is just plainly 
bogus. Related to both PR 100 and bug 12272.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
  BugsThisDependsOn|                            |100, 12272
           Severity|normal                      |enhancement
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
           Keywords|                            |diagnostic
   Last reconfirmed|0000-00-00 00:00:00         |2005-03-02 23:01:37
               date|                            |
            Summary|namespace name lost         |ambiguous namespace and
                   |                            |diagnostic, unamed namespace


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20293

[Bug c++/20293] [3.4/4.0/4.1 regression] Wrong diagnostic for ambiguous access

[bangerth at dealii dot org]

------- Additional Comments From bangerth at dealii dot org  2005-03-02 23:03 -------
This is indeed a diagnostic problem: the access is ambiguous, but instead 
of saying so gcc chooses to mention that there is no such name at all. This 
happens in many places, and I believe that there must be at least half 
a dozen PRs about this. 
 
This is in fact also a regression, since before the new parser we got this: 
 
g/x> /home/bangerth/bin/gcc-3.3*/bin/c++ -c x.cc 
x.cc: In function `int main()': 
x.cc:16: error: use of `hide' is ambiguous 
x.cc:1: error:   first declared as `hide' here 
x.cc:7: error:   also declared as `<unnamed>::hide' here 
x.cc:16: error: parse error before `::' token 
 
icc says this: 
g/x> icc -c x.cc 
x.cc(16): error: "hide" is ambiguous 
      F(hide::j); 
        ^ 
 
compilation aborted for x.cc (code 2) 
 
W. 

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
  BugsThisDependsOn|100, 12272                  |
           Severity|enhancement                 |normal
      Known to fail|                            |3.4.3 4.0.0 4.1.0
      Known to work|                            |2.95 3.2 3.3
   Last reconfirmed|2005-03-02 23:01:37         |2005-03-02 23:03:15
               date|                            |
            Summary|ambiguous namespace and     |[3.4/4.0/4.1 regression]
                   |diagnostic, unamed namespace|Wrong diagnostic for
                   |                            |ambiguous access
   Target Milestone|---                         |3.4.4


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20293

[Bug c++/20293] [3.4/4.0/4.1 regression] Wrong diagnostic for ambiguous access

[giovannibajo at libero dot it]

------- Additional Comments From giovannibajo at libero dot it  2005-03-02 23:24 -------
(merging bugzilla conflicts...)

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
  BugsThisDependsOn|                            |100, 12272


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20293

[Bug c++/20293] [3.4/4.0/4.1 regression] Wrong diagnostic for ambiguous access

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2005-03-08 02:31 -------
The diagnostic changed when the new parser was merged in (between 20021213 and 20021228).

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20293

[Bug c++/20293] [3.4/4.0/4.1 regression] Wrong diagnostic for ambiguous access

[lerdsuwa at gcc dot gnu dot org]

------- Additional Comments From lerdsuwa at gcc dot gnu dot org  2005-03-11 16:27 -------
The diagnostic is missing due to calling lookup_name_real inside
cp_parser_lookup_name without the LOOKUP_COMPLAIN flag.  Too bad
we cannot just add this flag because this will cause duplicate
error messages.  cp_parser_lookup_name are called multiple times
during tentative parse.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20293

[Bug c++/20293] [3.4/4.0/4.1 regression] Wrong diagnostic for ambiguous access

[mmitchel at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|3.4.4                       |3.4.5


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20293

[Bug c++/20293] [3.4/4.0/4.1 regression] Wrong diagnostic for ambiguous access

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2005-07-22 21:13 -------
Moving to 4.0.2 pre Mark.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|3.4.5                       |4.0.2


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20293

[Bug c++/20293] [3.4/4.0/4.1 regression] Wrong diagnostic for ambiguous access

[bangerth at dealii dot org]

-- 
Bug 20293 depends on bug 100, which changed state.

Bug 100 Summary: confusing name lookup diagnostic
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=100

           What    |Old Value                   |New Value
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20293

[Bug c++/20293] [3.4/4.0/4.1 regression] Wrong diagnostic for ambiguous access

[mmitchel at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.0.2                       |4.0.3


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20293

[Bug c++/20293] [3.4/4.0/4.1 regression] Wrong diagnostic for ambiguous access

[mmitchel at gcc dot gnu dot org]

------- Comment #8 from mmitchel at gcc dot gnu dot org  2005-11-14 01:45 -------
Subject: Bug 20293

Author: mmitchel
Date: Mon Nov 14 01:45:19 2005
New Revision: 106879

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=106879
Log:
        PR c++/20293
        * cxx-pretty-print.c (pp_cxx_statement): Print qualifying scopes
        for namespaces.
        (pp_cxx_original_namespace_definition): Likewise.
        * name-lookup.c (ambiguous_decl): Don't issue error messages;
        instead return lists of ambiguous candidates.
        (select_decl): Handle ambiguous namespace lookups.
        * parser.c (cp_token): Add ambiguous_p.
        (cp_lexer_get_preprocessor_token): Set it.
        (cp_parser_diagnose_invalid_type_name): Avoid duplicate messages
        when a qualified name uses an invalid scope. 
        (cp_parser_primary_expression): Print ambiguous candidates.
        (cp_parser_type_parameter): Adjust comment to reflect new
        parameter name for cp_parser_lookup_name.
        (cp_parser_template_argument): Likewise.
        (cp_parser_elaborated_type_specifier): Likewise.
        (cp_parser_namespace_name): Likewise.
        (cp_parser_class_name): Print ambiguous candidates.
        (cp_parser_lookup_name): Rename ambiguous_p parameter to
        ambiguous_decls.  Use it to return a list of ambiguous candiates
        when a lookup is ambiguous.
        (cp_parser_lookup_name_simple): Adjust comment to reflect new
        parameter name for cp_parser_lookup_name.

        PR c++/20293
        * g++.dg/parse/ambig4.C: New test.
        * g++.dg/tc1/dr101.C: Adjust error markers.
        * g++.dg/lookup/strong-using-2.C: Likewise.
        * g++.dg/lookup/ambig5.C: Likewise.
        * g++.dg/lookup/ambig4.C: Likewise.
        * g++.dg/parse/crash22.C: Likewise.

Added:
    trunk/gcc/testsuite/g++.dg/parse/ambig4.C
Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/cxx-pretty-print.c
    trunk/gcc/cp/name-lookup.c
    trunk/gcc/cp/parser.c
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/g++.dg/lookup/ambig4.C
    trunk/gcc/testsuite/g++.dg/lookup/ambig5.C
    trunk/gcc/testsuite/g++.dg/lookup/strong-using-2.C
    trunk/gcc/testsuite/g++.dg/parse/crash22.C
    trunk/gcc/testsuite/g++.dg/tc1/dr101.C


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20293

[Bug c++/20293] [3.4/4.0/4.1 regression] Wrong diagnostic for ambiguous access

[mmitchel at gcc dot gnu dot org]

-- 

mmitchel at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |mark at codesourcery dot com
                   |dot org                     |
             Status|NEW                         |ASSIGNED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20293

[Bug c++/20293] [3.4/4.0/4.1 regression] Wrong diagnostic for ambiguous access

[mmitchel at gcc dot gnu dot org]

------- Comment #7 from mmitchel at gcc dot gnu dot org  2005-10-31 02:49 -------
Leaving as P2; we should try to fix this.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20293